xref: /dragonfly/contrib/gcc-4.7/gcc/genconfig.c (revision 926deccb)
1 /* Generate from machine description:
2    - some #define configuration flags.
3    Copyright (C) 1987, 1991, 1997, 1998, 1999, 2000, 2003, 2004, 2007, 2010
4    Free Software Foundation, Inc.
5 
6 This file is part of GCC.
7 
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
12 
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
16 for more details.
17 
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3.  If not see
20 <http://www.gnu.org/licenses/>.  */
21 
22 
23 #include "bconfig.h"
24 #include "system.h"
25 #include "coretypes.h"
26 #include "tm.h"
27 #include "rtl.h"
28 #include "errors.h"
29 #include "gensupport.h"
30 
31 
32 /* flags to determine output of machine description dependent #define's.  */
33 static int max_recog_operands;  /* Largest operand number seen.  */
34 static int max_dup_operands;    /* Largest number of match_dup in any insn.  */
35 static int max_clobbers_per_insn;
36 static int have_cc0_flag;
37 static int have_cmove_flag;
38 static int have_cond_exec_flag;
39 static int have_lo_sum_flag;
40 static int have_peephole_flag;
41 static int have_peephole2_flag;
42 
43 /* Maximum number of insns seen in a split.  */
44 static int max_insns_per_split = 1;
45 
46 /* Maximum number of input insns for peephole2.  */
47 static int max_insns_per_peep2;
48 
49 static int clobbers_seen_this_insn;
50 static int dup_operands_seen_this_insn;
51 
52 static void walk_insn_part (rtx, int, int);
53 static void gen_insn (rtx);
54 static void gen_expand (rtx);
55 static void gen_split (rtx);
56 static void gen_peephole (rtx);
57 static void gen_peephole2 (rtx);
58 
59 /* RECOG_P will be nonzero if this pattern was seen in a context where it will
60    be used to recognize, rather than just generate an insn.
61 
62    NON_PC_SET_SRC will be nonzero if this pattern was seen in a SET_SRC
63    of a SET whose destination is not (pc).  */
64 
65 static void
66 walk_insn_part (rtx part, int recog_p, int non_pc_set_src)
67 {
68   int i, j;
69   RTX_CODE code;
70   const char *format_ptr;
71 
72   if (part == 0)
73     return;
74 
75   code = GET_CODE (part);
76   switch (code)
77     {
78     case CLOBBER:
79       clobbers_seen_this_insn++;
80       break;
81 
82     case MATCH_OPERAND:
83       if (XINT (part, 0) > max_recog_operands)
84 	max_recog_operands = XINT (part, 0);
85       return;
86 
87     case MATCH_OP_DUP:
88     case MATCH_PAR_DUP:
89       ++dup_operands_seen_this_insn;
90     case MATCH_SCRATCH:
91     case MATCH_PARALLEL:
92     case MATCH_OPERATOR:
93       if (XINT (part, 0) > max_recog_operands)
94 	max_recog_operands = XINT (part, 0);
95       /* Now scan the rtl's in the vector inside the MATCH_OPERATOR or
96 	 MATCH_PARALLEL.  */
97       break;
98 
99     case LABEL_REF:
100       if (GET_CODE (XEXP (part, 0)) == MATCH_OPERAND
101 	  || GET_CODE (XEXP (part, 0)) == MATCH_DUP)
102 	break;
103       return;
104 
105     case MATCH_DUP:
106       ++dup_operands_seen_this_insn;
107       if (XINT (part, 0) > max_recog_operands)
108 	max_recog_operands = XINT (part, 0);
109       return;
110 
111     case CC0:
112       if (recog_p)
113 	have_cc0_flag = 1;
114       return;
115 
116     case LO_SUM:
117       if (recog_p)
118 	have_lo_sum_flag = 1;
119       return;
120 
121     case SET:
122       walk_insn_part (SET_DEST (part), 0, recog_p);
123       walk_insn_part (SET_SRC (part), recog_p,
124 		      GET_CODE (SET_DEST (part)) != PC);
125       return;
126 
127     case IF_THEN_ELSE:
128       /* Only consider this machine as having a conditional move if the
129 	 two arms of the IF_THEN_ELSE are both MATCH_OPERAND.  Otherwise,
130 	 we have some specific IF_THEN_ELSE construct (like the doz
131 	 instruction on the RS/6000) that can't be used in the general
132 	 context we want it for.  */
133 
134       if (recog_p && non_pc_set_src
135 	  && GET_CODE (XEXP (part, 1)) == MATCH_OPERAND
136 	  && GET_CODE (XEXP (part, 2)) == MATCH_OPERAND)
137 	have_cmove_flag = 1;
138       break;
139 
140     case COND_EXEC:
141       if (recog_p)
142 	have_cond_exec_flag = 1;
143       break;
144 
145     case REG: case CONST_INT: case SYMBOL_REF:
146     case PC:
147       return;
148 
149     default:
150       break;
151     }
152 
153   format_ptr = GET_RTX_FORMAT (GET_CODE (part));
154 
155   for (i = 0; i < GET_RTX_LENGTH (GET_CODE (part)); i++)
156     switch (*format_ptr++)
157       {
158       case 'e':
159       case 'u':
160 	walk_insn_part (XEXP (part, i), recog_p, non_pc_set_src);
161 	break;
162       case 'E':
163 	if (XVEC (part, i) != NULL)
164 	  for (j = 0; j < XVECLEN (part, i); j++)
165 	    walk_insn_part (XVECEXP (part, i, j), recog_p, non_pc_set_src);
166 	break;
167       }
168 }
169 
170 static void
171 gen_insn (rtx insn)
172 {
173   int i;
174 
175   /* Walk the insn pattern to gather the #define's status.  */
176   clobbers_seen_this_insn = 0;
177   dup_operands_seen_this_insn = 0;
178   if (XVEC (insn, 1) != 0)
179     for (i = 0; i < XVECLEN (insn, 1); i++)
180       walk_insn_part (XVECEXP (insn, 1, i), 1, 0);
181 
182   if (clobbers_seen_this_insn > max_clobbers_per_insn)
183     max_clobbers_per_insn = clobbers_seen_this_insn;
184   if (dup_operands_seen_this_insn > max_dup_operands)
185     max_dup_operands = dup_operands_seen_this_insn;
186 }
187 
188 /* Similar but scan a define_expand.  */
189 
190 static void
191 gen_expand (rtx insn)
192 {
193   int i;
194 
195   /* Walk the insn pattern to gather the #define's status.  */
196 
197   /* Note that we don't bother recording the number of MATCH_DUPs
198      that occur in a gen_expand, because only reload cares about that.  */
199   if (XVEC (insn, 1) != 0)
200     for (i = 0; i < XVECLEN (insn, 1); i++)
201       {
202 	/* Compute the maximum SETs and CLOBBERS
203 	   in any one of the sub-insns;
204 	   don't sum across all of them.  */
205 	clobbers_seen_this_insn = 0;
206 
207 	walk_insn_part (XVECEXP (insn, 1, i), 0, 0);
208 
209 	if (clobbers_seen_this_insn > max_clobbers_per_insn)
210 	  max_clobbers_per_insn = clobbers_seen_this_insn;
211       }
212 }
213 
214 /* Similar but scan a define_split.  */
215 
216 static void
217 gen_split (rtx split)
218 {
219   int i;
220 
221   /* Look through the patterns that are matched
222      to compute the maximum operand number.  */
223   for (i = 0; i < XVECLEN (split, 0); i++)
224     walk_insn_part (XVECEXP (split, 0, i), 1, 0);
225   /* Look at the number of insns this insn could split into.  */
226   if (XVECLEN (split, 2) > max_insns_per_split)
227     max_insns_per_split = XVECLEN (split, 2);
228 }
229 
230 static void
231 gen_peephole (rtx peep)
232 {
233   int i;
234 
235   /* Look through the patterns that are matched
236      to compute the maximum operand number.  */
237   for (i = 0; i < XVECLEN (peep, 0); i++)
238     walk_insn_part (XVECEXP (peep, 0, i), 1, 0);
239 }
240 
241 static void
242 gen_peephole2 (rtx peep)
243 {
244   int i, n;
245 
246   /* Look through the patterns that are matched
247      to compute the maximum operand number.  */
248   for (i = XVECLEN (peep, 0) - 1; i >= 0; --i)
249     walk_insn_part (XVECEXP (peep, 0, i), 1, 0);
250 
251   /* Look at the number of insns this insn can be matched from.  */
252   for (i = XVECLEN (peep, 0) - 1, n = 0; i >= 0; --i)
253     if (GET_CODE (XVECEXP (peep, 0, i)) != MATCH_DUP
254 	&& GET_CODE (XVECEXP (peep, 0, i)) != MATCH_SCRATCH)
255       n++;
256   if (n > max_insns_per_peep2)
257     max_insns_per_peep2 = n;
258 }
259 
260 int
261 main (int argc, char **argv)
262 {
263   rtx desc;
264 
265   progname = "genconfig";
266 
267   if (!init_rtx_reader_args (argc, argv))
268     return (FATAL_EXIT_CODE);
269 
270   puts ("/* Generated automatically by the program `genconfig'");
271   puts ("   from the machine description file `md'.  */\n");
272   puts ("#ifndef GCC_INSN_CONFIG_H");
273   puts ("#define GCC_INSN_CONFIG_H\n");
274 
275   /* Allow at least 30 operands for the sake of asm constructs.  */
276   /* ??? We *really* ought to reorganize things such that there
277      is no fixed upper bound.  */
278   max_recog_operands = 29;  /* We will add 1 later.  */
279   max_dup_operands = 1;
280 
281   /* Read the machine description.  */
282 
283   while (1)
284     {
285       int line_no, insn_code_number = 0;
286 
287       desc = read_md_rtx (&line_no, &insn_code_number);
288       if (desc == NULL)
289 	break;
290 
291       switch (GET_CODE (desc))
292 	{
293   	  case DEFINE_INSN:
294 	    gen_insn (desc);
295 	    break;
296 
297 	  case DEFINE_EXPAND:
298 	    gen_expand (desc);
299 	    break;
300 
301 	  case DEFINE_SPLIT:
302 	    gen_split (desc);
303 	    break;
304 
305 	  case DEFINE_PEEPHOLE2:
306 	    have_peephole2_flag = 1;
307 	    gen_peephole2 (desc);
308 	    break;
309 
310 	  case DEFINE_PEEPHOLE:
311 	    have_peephole_flag = 1;
312 	    gen_peephole (desc);
313 	    break;
314 
315 	  default:
316 	    break;
317 	}
318     }
319 
320   printf ("#define MAX_RECOG_OPERANDS %d\n", max_recog_operands + 1);
321   printf ("#define MAX_DUP_OPERANDS %d\n", max_dup_operands);
322 
323   /* This is conditionally defined, in case the user writes code which emits
324      more splits than we can readily see (and knows s/he does it).  */
325   printf ("#ifndef MAX_INSNS_PER_SPLIT\n");
326   printf ("#define MAX_INSNS_PER_SPLIT %d\n", max_insns_per_split);
327   printf ("#endif\n");
328 
329   if (have_cc0_flag)
330     {
331       printf ("#define HAVE_cc0 1\n");
332       printf ("#define CC0_P(X) ((X) == cc0_rtx)\n");
333     }
334   else
335     {
336       /* We output CC0_P this way to make sure that X is declared
337 	 somewhere.  */
338       printf ("#define CC0_P(X) ((X) ? 0 : 0)\n");
339     }
340 
341   if (have_cmove_flag)
342     printf ("#define HAVE_conditional_move 1\n");
343 
344   if (have_cond_exec_flag)
345     printf ("#define HAVE_conditional_execution 1\n");
346 
347   if (have_lo_sum_flag)
348     printf ("#define HAVE_lo_sum 1\n");
349 
350   if (have_peephole_flag)
351     printf ("#define HAVE_peephole 1\n");
352 
353   if (have_peephole2_flag)
354     {
355       printf ("#define HAVE_peephole2 1\n");
356       printf ("#define MAX_INSNS_PER_PEEP2 %d\n", max_insns_per_peep2);
357     }
358 
359   puts("\n#endif /* GCC_INSN_CONFIG_H */");
360 
361   if (ferror (stdout) || fflush (stdout) || fclose (stdout))
362     return FATAL_EXIT_CODE;
363 
364   return SUCCESS_EXIT_CODE;
365 }
366